1. Field of the Invention
The present invention generally relates to dynamic load balancing in a wireless communication network. In particular, the present invention relates to dynamic load balancing by altering the coverage areas and optionally altering network parameters such as frequencies of one or a plurality of coverage areas.
2. Description of the Related Art
Network planning relies on static approaches for site locations and dimensioning of the radio resources to meet a specified traffic demand at busy hours. Dimensioning fixed resources to satisfy traffic demand for busy hours is an ineffective planning practice and is very expensive for service providers since the resources for every site are often over estimated to meet traffic demand that may occur only in limited time durations.
Apart from optimizing the hardware resources, service providers have to dramatically reduce interference in their network to maximize the number of subscribers and/or the quality that those subscribers can achieve. Smart antennas were the leading technology and have been considered for IEEE802.16e-2005 and 3GPP LTE standards. Smart antennas or adaptive beamforming use a plurality of antennas to null interferers or track a desired subscriber by means of a narrow beam. However, complex signal processing is required in the base stations, which increases the cost of wireless equipment. Adaptive digital beamforming, as described in IEEE802.16e-2005 for example, is implemented for each subscriber in a cell.
The above standard (i.e., IEEE802.16e-2005) describes generally ways for setting up the best radiation pattern from base stations to a mobile subscriber and tracking it if necessary according to its mobility in the cell. However, detailed implementation is left unspecified by the standard. Additionally, because of the complexity of the implementation, most of base station vendors have decided not to implement beamforming in their initial products. Initial deployments of products have been more focused on demonstrating the basic features of the broadband technology rather than optional features such as beamforming.
Therefore, it would be useful to implement an apparatus that can dynamically adjust radio resources and network parameters to match a time varying traffic demand. Additionally, it would be useful to use one or more antennas to create multiple coverage areas that are optimized according to actual user distribution in the wireless communication network and to achieve interference reduction capability by narrowing down coverage areas, while deploying standard base stations rather than new ones that are equipped with adaptive beamforming capability.